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arXiv · 1203.1928

A robust constraint on cosmic textures from the cosmic microwave background

Stephen M. Feeney·Matthew C. Johnson·Daniel J. Mortlock·Hiranya V. Peiris
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Abstract

Fluctuations in the cosmic microwave background (CMB) contain information which has been pivotal in establishing the current cosmological model. These data can also be used to test well-motivated additions to this model, such as cosmic textures. Textures are a type of topological defect that can be produced during a cosmological phase transition in the early universe, and which leave characteristic hot and cold spots in the CMB. We apply Bayesian methods to carry out a rigorous test of the texture hypothesis, using full-sky data from the Wilkinson Microwave Anisotropy Probe. We conclude that current data do not warrant augmenting the standard cosmological model with textures. We rule out at 95% confidence models that predict more than 6 detectable cosmic textures on the full sky.

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Stephen M. Feeney, Matthew C. Johnson, Daniel J. Mortlock, Hiranya V. Peiris. 2012-05-28. A robust constraint on cosmic textures from the cosmic microwave background. https://doi.org/10.1103/physrevlett.108.241301

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